diff -r 000000000000 -r 6474c204b198 browser/components/tabview/test/browser_tabview_bug595521.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/components/tabview/test/browser_tabview_bug595521.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,67 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+let fadeAwayUndoButtonDelay;
+let fadeAwayUndoButtonDuration;
+
+function test() {
+  waitForExplicitFinish();
+
+  window.addEventListener("tabviewshown", testCloseLastGroup, false);
+  TabView.toggle();
+}
+
+function testCloseLastGroup() {
+  window.removeEventListener("tabviewshown", testCloseLastGroup, false);
+  ok(TabView.isVisible(), "Tab View is visible");
+
+  let contentWindow = document.getElementById("tab-view").contentWindow;
+
+  is(contentWindow.GroupItems.groupItems.length, 1, "Has one group only");
+
+  let groupItem = contentWindow.GroupItems.groupItems[0];
+  
+  let checkExistence = function() {
+    is(contentWindow.GroupItems.groupItems.length, 1, 
+       "Still has one group after delay");
+
+    EventUtils.sendMouseEvent(
+      { type: "click" }, groupItem.$undoContainer[0], contentWindow);
+  };
+
+  groupItem.addSubscriber("groupHidden", function onHidden() {
+    groupItem.removeSubscriber("groupHidden", onHidden);
+    // it should still stay after 3 ms.
+    setTimeout(checkExistence, 3);
+  });
+
+  groupItem.addSubscriber("groupShown", function onShown() {
+    groupItem.removeSubscriber("groupShown", onShown);
+
+    let endGame = function() {
+      window.removeEventListener("tabviewhidden", endGame, false);
+      ok(!TabView.isVisible(), "Tab View is hidden");
+
+      groupItem.fadeAwayUndoButtonDelay = fadeAwayUndoButtonDelay;
+      groupItem.fadeAwayUndoButtonDuration = fadeAwayUndoButtonDuration;
+
+      finish();
+    };
+    window.addEventListener("tabviewhidden", endGame, false);
+
+    TabView.toggle();
+  });
+
+  let closeButton = groupItem.container.getElementsByClassName("close");
+  ok(closeButton, "Group item close button exists");
+
+  // store the original values
+  fadeAwayUndoButtonDelay = groupItem.fadeAwayUndoButtonDelay;
+  fadeAwayUndoButtonDuration = groupItem.fadeAwayUndoButtonDuration;
+
+  // set both fade away delay and duration to 1ms
+  groupItem.fadeAwayUndoButtonDelay = 1;
+  groupItem.fadeAwayUndoButtonDuration = 1;
+
+  EventUtils.sendMouseEvent({ type: "click" }, closeButton[0], contentWindow);
+}